Further characterization of ATPases present in corneal endothelial, plasma membranes will be carried out. Such membranes are thought to be sites of deturgescence in the cornea. Additional marker enzymes will be assayed to further assure the purity of these preparations. Investigations will continue on the preparation of endothelial cells devoid of Descemet's membrane in order to be able to assay the sulfhydryl population present in the plasma membranes of these cells. Assay of ATPases with some metabolites known to ameliorate deturgescence will be accomplished.